Flash-light lamp



P. VIERKTTER FLASH LIGHT LAMP Filed neg. 29. 192s April 19, 1927.`

FIGA, FIG. 2

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Ly' j lll Patented -April 19, 1927.

UNITED ,STATES nur. vraax'r'rnn, or normar, GERMANY.

nasa-mear nur.

Application led December 29,

' With all known flash-light lamps, the explosive charge burns with an open ame which necessitates the provision of special safet' devices in order to` revent tires. If pow er mixtures are use they y'must be prepared immediately before use as the finished mixture soon loses its effectiveness in the air. Combustion takes place in an ex' plosive manner with more or less noise which is apt to startle the observers. The' flame is not uniform, and it grows so big that-it is ditl'icult or even impossible to, distribute the light by means'of a diaphragmor a relector. The cloud of smoke and vapor aris ing during thefcombustion becomes distributed about the room and impairs visibility,

' so that it is nearly impossible to make sevthis purpose the hausted of air, or at least partly so.

consequence of the combustion of the flashyeral exposuresi'one after another in a small closed room.-' The combustion gases are, besides, harmful tothe respiratory organs.

The object of the present invention is to avoid the drawbacks from which the flashlight lamps with open flamev suffer, and for rflash-light substance or charge is enclosed in. a transparent hollow body which is practically completely rlelzlze combustion takes place, therefore, in a closed space and there is no longer any danger whatever otvfires.4 Burstin of the lamp in light substance cannot occur because there Vis either practically no air at all within the.

lamp, or itsamount is so small that no heating and expansion worth mentioning are caused. The ame is restricted to the narrow space within the lamp; andthis being so, there is produced a kind of globe orl ball of light of very great illuminating intensity, the'li ht rays from which can be directed or re ected to any desired place by means of a l:creen attached directly to the lamp. The detonating noise is obviated, as sound is not propagated in vacuo. The combustion gases cannot escape from the lamp but precipitate on the inner wall of the same, an it is, therefore, possibleto make use of as j many flash-light exposures as desired, one

after another, without impairing the transparenc of the air and acting detrimentally upon t e respira-tory organs. w

If a flash-light powder'is employed, there is no danger of its eiectiveness decreasing, as the ver small amount of air still contained in t e lamp is of no consequence. It

is a matter of course that only such sub- 1926), Serial No. 157,844, and in Germany Agult 1l, 1985.

stances y'can be used for Hash-li ht purposes 1n vacuo as can be admixed witl peroxide, ammonium nitrate or the like.

'l hc manner 1n which combustion occurs-can be influenced by the introduction of a rarel fied gas in such away that explosions do not take placefand that combustion is promoted. The ignition of the charge caneffected in' several ways, for instance chemically or mechanically or by heating. Employ-'infr electricity for this purpose is par-- panying drawing in which Figure 1'is an axial section through a Hash-light lamp de- 0 an oxygenproducing substance, such as manganese signed according to this invent1on, ai 1d Figure 2 is a similar representation showing a modification, the difference residing chiefly inthat in Fig. 1' the lamp has one flash-light charge and in Fig.v 2 two such charges.

The improved .lamp resembles an ordinary electric' incandescent lamp. The tit/- ting 1 carries a glass bulb 2,v the lower end of which` is made integral with an upwardly directed projection 3 through which vpass conducting wires 4. vThe outer end of .one wire is conductively connected with themetallic fitting 1 at the point 5, and that of the other wire with the metallic contact disk' 6' which is insulated from said fitting. 7 is a small tube enclosed air-tight inthe projection 3 and servingfor exhausting the y.

bulb, and 8 is an asbestos disk which is 'ixed to saidprojection by means of pins i 9: The asbestos disk 8 is 4disposed within and firmly connected to a that extends'downwardl into the neck of the bulb 2 so that its ower portion surglass cylinder 10 rounds the head of the projection 3 and the portion of the cylinder 10 supports wit in 1t a small casing 11 holding the flash-light powder 12; and this casing must be so cond xfree portions of the wires 4. The up er l i gas pressure that arises instantll after the for w ich purpose the annular side wall `of thecasing, the closing disk13 and the bottom disk14 are merely glued connected ina similar manner; he parts to'lgether yor f formin thecasing or receptacle 11 consist prefera ly of asbestos or glass and are as thin aspossible. The disk 13 bears .upon the rim of the glass c linder 10 and 1s cemented ,or similarly astened thereto; In

`order to prevent the lamp from being which extend down between the cylinder 10 and the asbestos disk 8, below which they` are connected with the current-carrying wires 4.

When the lamp is screwed into a socket and the current is switched on, the fiashlight charge is exploded instantaneously by the glowing spiral 15. The receptacle 11, 13, 14 is destroyed at once as it presents practically no resistance to the gases generated at the moment of the explosion. The burning gases can spread freely to -all sides and form, as it were, an intensely luminous ball. As the bulb is evacuated, it is prevented from being destroyed by an increase of pressure resulting fromrt e gases enclosed within it. The glass projection 3 and the curi-entsupplying wires 4 are protected by the lower ortion of the glass cylinder 10 so that sai projection is prevented from being shattered, and said wires from being shortcircuited, by the fiame. As .the flame arising when the combustion takes place forms a conductor for the current, ,the amount of current increases in such a measure that the spiral 15 melts through, whereby the -cir- .cuit is broken automatically and the fuses in the circuit are prevented from disruption. In order to obtain an' instantaneous ignition the ignition wire or spiral must be able to stand as high a temperature as posible before melting; suitable materials for it are iron, tungsten, tantalum and molybdenum.

The effectiveness of the lamp, as de? scribed, depends upon the maintenance of the vacuum, and means must, therefore, be provided by which the circuit is broken automatically if it should happen that the vacuum is destroyed from any cause. In.

the example shown a capillary tube 16 is inserted into the asbestos disk 8. 'This tube isclosed at its upper end andopen at its lower end, and the uppermost portion of the interior of the tube is separatedV from the portion below by a drop 17 of mercury,

whereby a certain small amount of air is kept enclosed in the aforesaid ortion of the tube 16.' The current-supp ying wire capillary tube an'd 'contacts finally with the wire ends mentioned, whereby these are -conductively connected with'each other. If-

the lamp should become leaky, the mercury drop will be forced upwardly in the tube away from the wire ends in question by the pressure of the in-coming air, so that the circuit is broken and the flash-light charge cannot be exploded. v

When a flash-light charge has beeny exploded, lthe lamp will be ready for the ex-A plosion of another .charge as soon as the combustion gases have condensed, so that it is possible to employ a lamp for a succession of flash-light exposures. In other words: there maybe made lamps containing a plurality' of flash-light charges, but

then provision must .be made for preventing the other charge or charges from exploding when the first charge 1s ignited.

A Hash-light lamp answering this requirement and-intended for two exposures is illustrated in Fig. 2. 18 and 19 indicate the two- Hash-light charges which are separated from each other by a mica wall 20. Each charge is carried by a supporting device similar to that described in connection with Fig. l (glass cylinder, asbestos disk, and so ou); and these two devices are supported by a wire bow 23 serving also as common current 28 and 29 which are insulate'd'from each other by an insulating disk 30. The common bow 23 is conductively connected with the fitting 27 at the point 26, There are two circuits: the first: 27, 26, 23, 22, 25, 28; the second: 27, 26, 21, 24, 29. This latter circuit is used first. lVhen the charge 18 has been ignited, the combustion gaseshave condensed, and the lamp has cooled down, the lamp is unscrewed from -the socket (not shown) and the contact disk 29 and the insulating disk 30 are torn off, whereafter the lamp is again screwed into the sockct'so that now the other circuit can be closed in order to explode the other flash-light charge.

As the combustion takes place in the closed' isa (Fig. 1) or 27 (Fig. 2) by means of a ring 32 that is shoved over the respective fitting and is clamped fast, after having been properly adjusted, between the fitting and the socket when the'fitting is screwed home in the socket. e

I claim as my invention v 1. A Hash-light lamp, comprising, in combination, a hollow, transparent body which is at least partially evacuated, a carrier for; a flash-light charge enclosed in ysaid body, and means forexploding said charge within the said body.

2. A flash-light 1an'1p, comprising', in combination,a hollow, transparent body, filled with a gas, the pressure of which is below that of the atmosphere, a carrier for a fiashlight charge enclosed in said body, and means for explodinglsaid charge within thesaid body.

3. A Hash-light lamp, comprising, in combination, a glass bulb which is at least partially evacuated, a fitting firmly connected with one end of said bulb, aprojection inteoral with the bulb `and extending centrally from said fitting into the bulb, contact-menibers at said fitting, conduct-ing wires extending from said contact members' through/said projection into-said bulb, a carrier for a. fiash-lightmharge enclosed in the bulb, vand electric means for exploding said charge within the bulb, said exploding means being conductively connected with said wires.

4. A flash-light lamp, comprising, in combination, a glass bulb which is atleast partially evacuated, a .fitting firmly connected with one end of said bulb, a4 projection integral with the bulb'aiid extending centrally i from said fitting into the bulb, an exhausting tube extending `through said projection and sealed therein, contact-members at said fitting, conducting' wires extending trom said contact members through said projection into the said bulb, a carrier for a Hash-light charge enclosed in the bulb, and electric means for exploding said charge within the bulb, said exploding means being conductively connectedwith said wires. i

5. A flash-light lamp. comprising, in combination, a glass bulb which is at least partially evacuated, a fitting firmly connected with one end ot said bulb, a projection integral with the bulb and extending centrally from said fitting into the bulb, contact members at said fitting, conducting wires extending from said Contact members through said projection into the said bulb, a carrier for a flash-light charge. enclosed in the bulb, a. disk connected to said projection, a glass tube enclosing said disk and supporting said carrier, and electric means for exploding said charge, the current-supplying wires comprising an which connect the exploding means with the said contact members being clamped between said disk and said glass tube.

6. A Hash-light lamp, comprising, in combination, a hollow, transparent body which is at least partially adapted to contain a Hash-light charge and consisting of a material presenting practically no resistance to.v the explosion gases,v and means for exploding said charge within the said body.

7. A flash-licht lamp, comprising, in combination, a hollow transparent body which is at least partially adapted tocontaina flash-light 'cliarve and annularbody and a bottom disk and a top disk, and means for exploding said charge within the said body.

8. A flash-light lamp, comprising, in combination, a glass bulb which is at least par,

tially evacuated, a fitting firmly connected with one end of tegral with the bulb and extending centrally from said fitting'into the bulb, contact members at said fitting, conductingw'ires extending from said contact members through said projection into the said bulb, a receptacle adapted 'to contain a Hash-light charge and comprising an annular body and top and bottom disks, a glass .cylinder enclosing said receptacleand cemented at its upper end tothe rim of the top disk, and means lfo1 exploding said charge withinv the said 0 9.y A flash-li ht lamp, comprising, in combination, a ho low, transparent body which is Aat least partially evacuated. a receptacle adapted to contain a fiasli-light char e and comprising an annular body and a ottom disk anda top disk, and electric means for exploding said charge and including cur,

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evacuated, .a receptacle evacuated, a receptacle Y said bulb. va projection in- A 'i rent-supplying wires one of which is tacle.

10. A flash-light llamp, comprising, in combination, aglass bulb which is-at least partially nected with one end of said bulb, a projection integral with the bulb and extending 1 centrally from said fitting into the bulb, contact members at said fitting, conducting wiresextending from said contact .members through said projection into the said' bulb,

a carrier to a Hash-light charge enclosed in the bulb, d an ignition wire embedded in said char e and consisting of a metal having a high fusing point, the sectional area of said wire being such that it melts through when the chargeis ignited and exploded.

11. A Hash-light lamp, comprising, in

evacuated, a fitting'` firmly conl combination, a glass bulb which is at least partially evacuated, a fitting firmly connected with one end of said bulb, a projection integral with the bulb and extending centrally from said fitting into the bulb,

'contact members at said fitting, conducting wires extending from said contact members through said projection into the said bulb, a carrier for a flash-light charge enclosed in the bulb, a disk connected to said projection, a capillary tube extending through said disk and being open at its lower end and closed at its upper end, a drop of mercury enclosed in said tube and enclosing in turn a small volume of air between it and said closed tube end, a glass tube enclosing said disk vand supporting said carrier, and electric means for exploding said charge, one of the current-supplying wlres connecting said exploding means with the said Contact members being cut through and the ends'at the place of cutting being inserted into the open end of the said capillary tube.

12. A flash-light lamp, comprising, in combination, a glass bulb which is atleast partially evacuated, a fitting firmly connected with one end of said bulb, a projection integral with the bulb and extending centrally from said fitting into the bulb, contact members atsaid fitting, conducting wires extending from said contact members through said projection into the said bulb, a plurality of carriers for flash-light charges enclosed 1n the bulb, screening means etween the individual carriers, electric means for exploding said charges one after another, a common conducting wire connecting all the charges with said fitting,a separate contact individual to each charge and associated with the fitting, and individual conducting wires connecting said separate contacts with the respective charges.

13. A flash-light lamp, comprising, in combination, a hollow, transparent body which is at least partially evacuated, a carrier for a flash-light charge enclosed in said body, means for exploding said charge within the said body, and a. turnable screen attached to the lamp. Y

' In testimony whereof I have affixed my signature.v

PAUL VIERKTTER.. 

